Testis morphology in rats chronically treated with letrozole, an aromatase inhibitor.

The aim of this study was to investigate the influence of the long-term treatment of rats with letrozole on the testis morphology. The pharmacologically induced estrogen deficiency caused statistically significant decreases of both intratesticular and serum levels of estradiol, and morphological changes in the seminiferous epithelium and in the interstitial tissue of the testes. Six months of treatment resulted in the sloughing of premature germ cells of the seminiferous epithelium into the tubular lumen and in intraepithelial vacuolization.

DHT deficiency perturbs the integrity of the rat seminiferous epithelium by disrupting tight and adherens junctions.

In rats with a DHT deficiency induced by finasteride, morphological changes in the seminiferous epithelium were observed. The structural alterations were manifested by the premature germ cells sloughing into the lumen of seminiferous tubules. The etiology of this disorder could be connected with intercellular junctions disintegration.

The expression of inducible nitric oxide synthase (iNOS) in the testis and epididymis of rats with a dihydrotestosterone (DHT) deficiency.

In our previous studies, we showed that a finasteride-induced DHT deficiency may cause changes in the morphology of the seminiferous epithelium without any morphological alteration of the epididymis. In this study, we demonstrated the constitutive immunoexpression of inducible nitric oxide synthase (iNOS) in the testis and epididymis of Wistar rats treated with finasteride for 28 days (the duration of two cycles of the seminiferous epithelium) and 56 days (the duration of one spermatogenesis). We noted that a 56-day finasteride treatment mainly caused a decrease in the level of circulating DHT, as well as a statistically insignificant decrease in the level of T.

Rat epididymal epithelial cells and 17beta-estradiol synthesis under hCG stimulation in vitro.

Epithelial cells of human and animal epididymis display features of steroidogenic cells. Rat epididymal epithelial cells in vitro produce androgens which are converted to 17beta-estradiol, and released into the medium. The regulation of the epididymal steroidogenesis is not fully understood but it could be expected that it remains under LH influence.

Hormonal status of male reproductive system: androgens and estrogens in the testis and epididymis. In vivo and in vitro approaches.

The purpose of this article was to summarize our results on the role of androgens and estrogens in human, rodent and equine testes and epididymides, in both, physiological and patological conditions, obtained in the space of the Solicited Project (084/PO6/2002) financially supported by the State Committee for Scientific Research during the last three years. Testosterone produced by Leydig cells of the testes is clearly the major androgen in the circulation of men and adult males of most mammalian species. However, androgen metabolites make up a significant fraction of total circulating steroids.